Motor-driven fan unit for use in vacuum cleaners



Feb, 6, 3953 F. T. SMITH 2,540,178

" MOTOR-DRIVEN FAN UNIT FOR USE IN VACUUM CLEANERS Filed NOV. 5, 1947 3 Shee tsSheet l INVENTOR. Wig/a 3 87922773 WI'ZIVESS BY f &; 4 A

cfffncaw ATTORNEY MOTOR-DRIVEN FAN UNIT FOR USE IN VACUUM CLEANERS Fil ed NOV. 5, 1947 F. T. SMETH Feb, a ma 3 Sheets-Sheet 2 MTNESS JP. 2Q; 76406 ATTORNEY m, 9 1951 F. T. SMITH WWW MOTOR-DRIVEN FAN UNIT FOR USE IN VACUUM CLEANERS Filed Nov. 5, 1947 3 Sheets-Sheet 3 IN VEN TOR.

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Singer Manufaeturhi: Company,

.The Elisabeth,

N. J., a corporation of New Jersey Application November 5, 1947;8erlal No, 784,185 I 6 Claims- (01. 230-111).

This invention relates to electric vacuum.

cleaners and more 'particularly to an electric motor-driven fan unit especially adapted though not necessarily restricted for use in vacuum cleaners.

A United States patent application Serial No.

184,167, filed November 5, 1947, by E. P. Turner,

describes and claims a vacuum cleaner arranged to support a motor-fan unit between upper and lower chassis members and arranged at the same time for pivotally mounting the handle of the vacuum cleaner on trunnions formed as part of the motor-fan unit. TheZmot r-fan .unit, housed between the upper and lower chassis members, described in the above noted application, may be any one of several different types but preferably it will be a motor-fan unit having a rotary fan housing formed on both ends I thereof and in which each of the fan-housings is formed with an outwardly extending trunnion that is coaxial with the motor shaft. The instant application has for one of its objects the provision of such an improved motor-fan unit which is especially adapted, though not necessarily restricted, to use in the vacuum cleaner arrangement set forth in the United States patent application Serial No. 784,167, supra.

Another object of the invention is toprovide an improved motor-fan unit having a motor located in a center position and a fan on each end thereof.

A still further object of the invention is to provide an improved motor-fan unit casing having2an exhaust duct, part of which is formed integral with the motor casing, and part of which is formed integral with the fan casing.

With the above, and other objects in view, as will hereinafter appear, the invention comprises the devices; combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

In the drawings Fig. 1 shows a top .plan view of a vacuum cleaner embodying this invention, the top shell being broken away to show the internal construction;

Fig. 2 is a sectional view of the cleaner an taken substantially along the line 2-2 of Fig. 1;

Fig. 3 is a bottom plan view of the vacuum cleaner shown in Figs. 1 and 2;

2' and 2. parts being broken nism shown in Figs. it

away and parts being in section to show the in-' ternal construction; and

Fig. 5 is-an exploded bottom perspective view showing portions of the motor-fan unit of this invention.

In the embodiment selected for illustration,

the invention is shown as applied'to'a vacuum cleaner having an ambulatory chassis in formed from a lower chassis shell II and an upper chassis shell l2; the two shells being joined on a line (Fig. 4) inclined slightly to the horizontal and indicated by the numeral l3. The lower shell II is held to the upper shell l2 by a screw ll that is rotatably supported in a pair of bosses I 6 formed integral with the lower shell H. The

threaded end of the screw it enters a threaded hole in a boss I! formed integral with the upper shell l2 and the lower end of the screw it is provided with a knurled head 18.

A combination electric motor and fan unit I! a is supported in the chassis l0, and the vacuum cleaner as a whole is supported on front and rear wheels 2| and 22. The front wheels are rotatably supported on axles secured to the lower chassis shell ll; whereas the rear wheels 22 are iou'maled on axles secured. to rearwardly extending exhaust duets 23, formedas part of the motor driven fan unit 19.

The upper chassis shell 12 has a front wall 26, side walls 21, a top wall 28 and rear wall portions 23. The top wall 28 has a centrally located cupola 3| which extends above the wall 28 and, when the vacuum cleaner is fully assembled, overlies the motor-fan unit l9. The cupola 3| has a back wall portion 32 which extends a short distance to the rear of the back wall por-' tion 29. The cupola 3| also-has a front wall 33 and a pair of side walls 34. The top wall 28 of the upper shell i2, where it is adjacent the side walls 34 of the cupola 3| is apertured by a pair of long narrow slots 35. The purpose of which will appear presently. The lower chassis shell H is substantially U-shaped (Fig. 3) in plan view and has a front wall 36, side walls 31, a bottom wall 38 and back wall portions 33. A forward portion of the bottom wall 38 is apertured to provide a suction mouth 4|. wall 36, the side walls 31 and the back walls 39 of the lower chassis shell II as well as the front wall 26 and part of the top wall 28 are covered with resilient material 42 which acts as a bumper. The bumpers (Fig. 1) are held to the Fig. 4 is a side elevational view of the mecha- I chassis to by means of resilient buttons 45 that The front abut on a plane 46, which'plane is perpendicular tothe central axis of the" motor-fan unit' IBWThis plane 48, as best seen in Figs. 1 and 3, also com- .cides with the longitudinal center lineof the the surface or end-face 13 of the end-bonnet 43. These protrudin blades are covered and housed by a cup-shaped fan casing 85 having a wall 81 composedof a spiral wall. 81*, a tangential wall 81 and a wal1.,81 that-is parallel tothe wall 81 These three walls 81, 81 and 81 are formed integral with the fan casing 85 and are complementaryto and have the same configuration asthe walls 11, and 11, respectively. The inner end of the wall 81 has a surface 88 vacuum cleaner and the vacuum cleaner handle.

The only portions of the vacuum cleaner handle shown in the drawings,- formin a part of this specification, are a pair of trunnion arms 48 and 58'; it being understood that the, remainder of the handle can be secured to these arms. The

end-bonnet 44 (Fig. 3) is provided with'a pair of downwardly facing slots 41 for ventilating the interior of the motor portion 48 of the unit I8.-

The end-bonnet 43 is provided with a pair of opposed holes 48 (Fig. 2) for accommodating a pair of conventional brush holders 5|. Each of the end-bonnets 43-44 has a concentrically apertured hub 52 and each apertured hub supports 'theouter race ring of a ball bearing. 53; the inner ture 56 and two suction producing fans 51 and 58, one at each end of the said shaft; the fans being held in place by set screws 88. Each fan has a cylindrical disc-like spider 59, a plurality of radially positioned blades BI, and the fan 51 has an extended hub 62 which provides a pulley for dniving a belt 63. The belt 63 drives a dust brush 84, which may be of conventional design. A third fan '38 mounted on the shaft 54 within the end-bonnets 44 perform the usual function of ventilating the motor 48. The end-bonnets 4344 are held together by a plurality of throughbolts 61, and when thus held support a field structure 88 that may be of conventional design.

The extreme end of the end-bonnet 43 (Fig. 5) is provided with a. flange H a portion of the outer periphery 12 of which is in the forni of a spiral. The end-face 13 of this flange, and therefore the end-face of the end-bonnet 43, is provided with a recess 14 a portion of the inner periphery '18 of which is in the form of a spiral that is concentric with the outer periphery 12. This forms an axially extending wall 11, a portion 11 of which is in the form of a spiral. A bottom surface 18 of the recess 14 is perpendicular to the motor shaft 54 and is provided with a circular recess 19 that is concentric with the bounded top and bottom by walls 11" and 11 and on one side by a side wall 86. These walls are all formed integral with. the end bell 43. The side wall 88 is positioned at an angle to the bottom surface 18 and is also at an angle to the shaft 54. The spider 58 of the fan 51 is of such diameter and axial thickness as to be of proper size as to just rotate in the recess 19. This allows the blade 6| and the hub of the fan to be positioned above the surface 18 of the recess 14, and since the recess 14 is comparatively shallow, the blades 51 extend a considerable distance beyond passageway from the fan 51.

- that conforms to and is matched to the surface. 13 on the end bonnet 43. The outer end of the casing 8,5 is closed by an outer wall 89 having an opening or fan eye" 8| that is concentric to the shaft 54. Atrunnion wall 92 is formed concentric with and completely encircles the eye 9!. The axial length of pulley hub 82 is such that it protrudes beyond the end of'the trunnion 82. The

wall 89, at a position indicated by the numeral 83, bends toward the surface 88 thus providing a slanting side wall 94 that is substantially though not exactly parallel to the wall 88 formed integral with the end-bonnet 43. The top wall 81*, the bottom wall 81 and the slanting wall 94 bound three sides of a portion 95 of the exhaust Both the endbonnet 43 and the fan casing 85 have a plurality of matched fastening lugs 96 which with the cooperation of a plurality of screws 91 hold the casing 85 to the end-bonnet 43. The fan casing 85 when secured to the end of the end-bonnet 43 provides a convenient and inexpensive means for housing the fan rotor 51. It also provides an intake port or eye SI and exhaust passageway; the latter being formed by the two portions of passageways 84 and 85. As best seen in Figs. 1 and 3, the duct or passageway 84-95 is at an acute angle to the axis end-bonnet 43 and the axis of the fan casing 85.

The end-bonnet 44, except for being opposite hand, is substantially of the same construction as the end-bonnet 43; the main difierence being in that end-bonnet 44 accommodates the head of the bolt 61 (Fig. 2), whereas the endbonnet 43 accommodates the threaded end thereof. The fan 58 differs from the fan 51 only in that it does not have the extended pulley hub 62. Also, in a manner similar to that previously described; a cup-shaped fan casing 98 is secured to the outer end of the end-bonnet 44. The casing 88, except for being opposite hand is the same as the previously described fan casing and this casing 98 provides a mean for housing the fan rotor 58 as well as an intake port or eye 88, a trumiion I88 and an exhaust duct formed by two portions I8! and I82. The eye 89 corresponds to the eye' 91 and the portions I8| and I82 correspond to the portions 84 and 85, respectively.

The means for mounting the above described motor-fan unit in a vacuum cleaner is described and claimed in the patent application Serial No. 184,167, supra. Briefly stated, however, this is accomplished by having the two opposite trunnions 92I88 clamped between the upper and lower chassis shells I2 and II which for this purpose are formed with a pair of semicircular trunnion engaging surfaces I86 and I81, respectively. The motor-fan unit is additionally secured to the upper chassis shell I2 by a pair of screws I88 which pass through holes formed in the motor-fan unit.

In addition to acting as a means for positioning and supporting the motor-fan unit inthe chassis I8, the two trunnions 82 and I88 provide a means for pivotally mounting the pair of trunnion arms 49 and 50 to which the handle of the vacuum clean r is attached. This is described and claimed in tie patengpplication Serial No. 784,167, supra. owever, it might be said that each trunnion armMS-BO is apertured by a circula'r hole I09 (Fig. 4). A composition bearingbushing III is press fitted into the hole I09, the internal diameter of the bushing 1' being of such a diameter as to be pivotally mounted on the outside of either the trunnion 92 or the trunnion I as the case may be.

From the above, it will be appreciated that thi invention has provided a combination motor and fan unit comprising the following elements assembled into one complete package; (a) a motor having a shaft, (1)) means for driving a belt from the shaft, (c) a pair of fans carried on opposite ends of'the shaft, (d) acasing for each of the fans, (e) an intake port or eye formed in each of the casings, and (I) an exhaust duct for each fan, part of the exhaust duct being formed integral with the motor and part integral with the fan casing and the two ducts converging toward one another, (9) means both for mounting and locating. the unit in a vacuum cleaner, and (h) means for ivotally mounting a handle.

The term trunnio as herein used, refers to the two opposite cylindrical projections or similar structures 92-!!! formed on opposite sides of the motor-fan unit IS. The term trunnion is'not intended to convey the idea that the motorfan unit turns on the trunnions as an axis. The trunnion arms 49 and 50 rotate with respect to the trunnions, but in the preferred form of construction there is no relative rotary motion between the trunnions and the chassis shells II and I2.

Having thus set forth the nature of the invention, what I claim herein is:

l. A combination motor-fan unit adapted for vacuum cleaners comprising a pair of motor enclosing end-bonnets clamped together; a motor shaft rotatably supported in said end-bonnets; a fan secured to opposite ends of said motor shaft; a separable fan casing enclosing each of said fans and each fan casing having an eye positioned axially with respect to said motor shaft, a trunnion surrounding each of said eyes and extending axially beyond the main body of said fan casing; and a pair of exhaust ducts having walls some of which are formed integral with said endbonnets and some of which are formed integra with said fan casings.

2. A combination motor-fan unit adapted for vacuum cleaners comprising a pair of motor enclosing end-bonnets clamped together; a motor shaft rotatably supported in said end-bonnets; a fan secured to opposite ends of said motor shaft; a' fan casing enclosing each of said fans and each fan casing having an eye positioned axially with respect to said motor shaft, a trunnion surrounding each of said eyes and extending axially beyond the main body of said fan casing; a pulley hub carried by one end of said shaft and exenclosing each fan formed integral therein; and a pair of exhaust ducts each having boundary walls, some of said walls of said exhaust du ts being formed integral with said end-bonnets nd otherof said walls of said exhaust ducts being formed integral with H said fan casings. 4. A motor-fan unit, comprising'a pair of concentrically apertured end-bonnets, a bearing carried in each of said apertured end-bonnets, a shaft rotatably carried in said bearings; a fan secured to each end of said shaft, a fan casing secured to the outer end of each of said endbonnets and enclosing said fan; each of said nets; a motor shaft rotatably supported in said end-bonnets; and each of said end-bonnets having a recess the bottom surface of which is perpendicular to said motor shaft; a fan secured to each end of said shaft; a peripheral wall spirally formed around a portion ofthe periphery of each of said recesses; a wall integral with each of said end-bonnets and formed tangent to each of said spirally formed wall; a second wall integral with each of said end-bonnets and formed parallel to each of said tangential walls; a side wall formed integral with and between each pair of said parallel walls, said side wall being inclined at an angle to 'said bottom surface and to said shaft; and a fan casing secured to the end-of each of said end-bonnets and covering each of said fans, each of said fan casings having a spiral wall, a tangent wall, and a parallel wall that are complements to similar walls on said end-bontending beyond the end of one of said trunnions;

and a pair of exhaust ducts having walls some of which are formed integral with said end-bonnets and some of which are formed integral with said fan casings.

nets and said fan casing also having a slanting side wall that is substantially parallel to said side wall on said end-bonnet.

6. A combination motor-fan unit adapted for vacuum cleaners comprising a pair of cup-shaped end-bonnets the lip portions of which abut one another; a motor shaft rotatably supported in said end-bonnets, and each of said end-bonnets having a recess the bottom surface of which is perpendicular to said motorshaft; a rotary fan secured to each end of said shaft and partly positioned in said recess; a peripheral wall integral with each of said 'end-bonnets and spirally formed around a portion of the periphery of each of said recesses; a wall integral with each of said end-bonnets and formed tangent to each of said spirally formed walls; a second wall integral with each of said end-bonnets and formed parallel to each of said tangent walls; a side wall formed integral with and between each pair of said parallel walls, said side wall being inclined at an angle to said bottom surface and to said shaft; and a cup-shaped fan casing secured to the end of each of said end-bonnets and cupped over each of said fans, each of said fan casings having a spiral wall, a tangent wall, and a parallel wall that are complements to similar walls on said end-bonnets and said fan casing, and also having a slanting side wall that is substantially parallel to said side wall on said endbonnet, whereby walls on said end-bonnets and said fan casings cooperate to form a pair of exhaust ducts that extend away from and at an and having an intake eye 8 angle to said motor shaft and which are con- UNITED STATES PATENTS versed toward one another. Numger Name Date 1,20 ,412 Tideman Nov. 21,1916 FLOYD SMITH' 5 1,542,597 Bates Jan. 16, 1925 REFERENCES CITED 2,140,143 Sellers et a1 Dec. 1a, 1938 The following references are of record in the file of this patent: 

